Employers can bar staff from wearing the headscarf and other religious symbols in the workplace, Europe's top court has ruled.

The European Court of Justice (ECJ) made the decision on the eve of a Dutch election in which Muslim immigration has been a key issue and a bellwether for attitudes to migration and refugee policies across Europe.

The ECJ gave a joined judgment in the cases of two women, in France and Belgium, who were dismissed for refusing to remove headscarves.

The Belgian court had referred the case to the EU's top court for clarification.

"An internal rule of an undertaking which prohibits the visible wearing of any political, philosophical or religious sign does not constitute direct discrimination," the Court said in a statement to the Telegraph.

"However, in the absence of such a rule, the willingness of an employer to take account of the wishes of a customer no longer to have the employer's services provided by a worker wearing an Islamic headscarf cannot be considered an occupational requirement that could rule out discrimination."